U.S. patent application number 14/502356 was filed with the patent office on 2015-07-30 for secondary battery.
The applicant listed for this patent is SAMSUNG SDI CO., LTD.. Invention is credited to Hyunsoo Lee, Janghyun Song.
Application Number | 20150214536 14/502356 |
Document ID | / |
Family ID | 51932223 |
Filed Date | 2015-07-30 |
United States Patent
Application |
20150214536 |
Kind Code |
A1 |
Lee; Hyunsoo ; et
al. |
July 30, 2015 |
SECONDARY BATTERY
Abstract
A secondary battery includes an electrode assembly comprising a
first electrode plate, a second electrode plate and a separator
located between the first electrode plate and the second electrode
plate; a case accommodating the electrode assembly; a cap plate
sealing the case; a first collector plate comprising a first
vertical part electrically connected to the first electrode plate,
a first horizontal part bent from the first vertical part and
extending between the electrode assembly and the cap plate, and a
first protrusion protruding from the first horizontal part; and a
first electrode terminal electrically connected to the first
collector plate and extending through the cap plate, wherein the
first electrode terminal has a coupling opening engaged with the
first protrusion.
Inventors: |
Lee; Hyunsoo; (Yongin-si,
KR) ; Song; Janghyun; (Yongin-si, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SAMSUNG SDI CO., LTD. |
Yongin-si |
|
KR |
|
|
Family ID: |
51932223 |
Appl. No.: |
14/502356 |
Filed: |
September 30, 2014 |
Current U.S.
Class: |
429/179 |
Current CPC
Class: |
H01M 2/30 20130101; Y02E
60/10 20130101; H01M 2/024 20130101; H01M 2/021 20130101; H01M 2/22
20130101 |
International
Class: |
H01M 2/30 20060101
H01M002/30; H01M 2/02 20060101 H01M002/02 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 28, 2014 |
KR |
10-2014-0010715 |
Claims
1. A secondary battery comprising: an electrode assembly comprising
a first electrode plate, a second electrode plate and a separator
located between the first electrode plate and the second electrode
plate; a case accommodating the electrode assembly; a cap plate
sealing the case; a first collector plate comprising a first
vertical part electrically connected to the first electrode plate,
a first horizontal part bent from the first vertical part and
extending between the electrode assembly and the cap plate, and a
first protrusion protruding from the first horizontal part; and a
first electrode terminal electrically connected to the first
collector plate and extending through the cap plate, wherein the
first electrode terminal has a coupling opening engaged with the
first protrusion.
2. The secondary battery as claimed in claim 1, wherein the first
protrusion is fixed to the first electrode terminal by
caulking.
3. The secondary battery as claimed in claim 1, wherein the first
protrusion protrudes toward the electrode assembly from a bottom
surface of the first horizontal part.
4. The secondary battery as claimed in claim 1, wherein the first
protrusion is parallel to the first vertical part.
5. The secondary battery as claimed in claim 1, wherein the first
electrode terminal comprises: a first terminal body passing through
the cap plate; and a first terminal extension part extending
perpendicularly from a lower portion of the first terminal
body.
6. The secondary battery as claimed in claim 5, wherein a stepped
part being thinner than the first terminal extension part is at one
side of the first terminal extension part, and wherein the coupling
opening is in the stepped part.
7. The secondary battery as claimed in claim 6, wherein the first
horizontal part is coupled to the stepped part.
8. The secondary battery as claimed in claim 6, wherein the first
horizontal part is coupled to the stepped part by laser
welding.
9. The secondary battery as claimed in claim 6, wherein a sum of a
thickness of the first horizontal part and a thickness of the
stepped part is equal to a thickness of the first terminal
extension part.
10. The secondary battery as claimed in claim 5, further comprising
a terminal plate coupled to the first terminal body, and wherein a
top portion of the first terminal body is riveted to be fixed to
the terminal plate.
11. The secondary battery as claimed in claim 1, further
comprising: a second collector plate including a second vertical
part electrically connected to the second electrode plate, a second
horizontal part bent from the second vertical part and extending
between the electrode assembly and the cap plate, and a second
protrusion protruding from the second horizontal part; and a second
electrode terminal electrically connected to the second collector
plate and extending through the cap plate, wherein the second
electrode terminal has a coupling opening engaged with the second
protrusion.
12. The secondary battery as claimed in claim 11, wherein the
second protrusion is fixed to the second electrode terminal by
caulking.
13. The secondary battery as claimed in claim 11, wherein the
second protrusion protrudes toward the electrode assembly from a
bottom surface of the second horizontal part.
14. The secondary battery as claimed in claim 11, wherein the
second protrusion is parallel to the second vertical part.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to and the benefit of
Korean Patent Application No. 10-2014-0010715 filed in the Korean
Intellectual Property Office on Jan. 28, 2014, the entire content
of which is incorporated herein by reference.
BACKGROUND
[0002] 1. Field
[0003] Embodiments relate to a secondary battery.
[0004] 2. Description of the Related Art
[0005] Generally, secondary batteries can be discharged and
recharged, unlike primary batteries, which are not rechargeable.
Secondary batteries may be of a low capacity type, which includes
battery cells in the form of a pack typically used for small
portable electronic devices such as cellular phones and camcorders,
or a high capacity type, which includes battery cells used as a
motor-driving power source and having several battery cells
connected to one another and widely used as a power source for
hybrid vehicles, etc.
[0006] Secondary batteries may be manufactured in various shapes,
such as cylindrical shape or prismatic shapes. A typical secondary
battery may include an electrode assembly having a positive plate
and a negative plate with a separator acting as an insulator
between the positive and negative plates accommodated in a battery
case with an electrolyte, and a cap assembly having electrode
terminals coupled to the case. The electrode assembly is
electrically connected to the electrode terminal through a current
collector. In that case, a volume of the case may vary according to
the connection structure of the current collector and the electrode
terminal. Therefore, it is necessary to manufacture a secondary
battery capable of implementing a higher capacity in a given
volume.
SUMMARY
[0007] Embodiments are directed to a secondary battery, which
represents and advance in the related art.
[0008] It is a feature of an embodiment to provide a secondary
battery, which can increase a capacity of an electrode assembly in
a given volume and can improve the reliability.
[0009] At least one of the above and other features and advantages
may be realized by providing a secondary battery includes an
electrode assembly including a first electrode plate, a second
electrode plate and a separator interposed between the first
electrode plate and the second electrode plate, a case
accommodating the electrode assembly, a cap plate sealing the case,
a first collector plate including a first vertical part
electrically connected to the first electrode plate, a first
horizontal part bent from an end of the first vertical part,
horizontally extending and formed between the electrode assembly
and the cap plate, and a first protrusion protruding from the first
horizontal part, and a first electrode terminal electrically
connected to the first collector plate and formed to pass through
the cap plate, wherein a coupling opening engaged with the first
protrusion is formed in the first electrode terminal.
[0010] After the first protrusion is engaged with the coupling
opening, it may be fixed to the first electrode terminal by
caulking.
[0011] The first protrusion may protrude toward the electrode
assembly from a bottom surface of the first horizontal part.
[0012] The first protrusion may be parallel to the first vertical
part.
[0013] The first electrode terminal may include a first terminal
body passing through the cap plate, and a first terminal extension
part horizontally extending from a lower portion of the first
terminal body.
[0014] A stepped part being thinner than the first terminal
extension part may be formed at one side of the first terminal
extension part, and the coupling opening may be formed in the
stepped part.
[0015] The first horizontal part may be coupled to the stepped
part.
[0016] The first horizontal part may be coupled to the stepped part
by laser welding.
[0017] A sum of a thickness of the first horizontal part and a
thickness of the stepped part may be equal to a thickness of the
first terminal extension part.
[0018] The secondary battery may further include a terminal plate
coupled to the first terminal body, and a top portion of the first
terminal body is riveted to be fixed to the terminal plate.
[0019] The secondary battery may further include a second collector
plate including a second vertical part electrically connected to
the second electrode plate, a second horizontal part bent from an
end of the second vertical part, horizontally extending and formed
between the electrode assembly and the cap plate, and a second
protrusion protruding from the second horizontal part, and a second
electrode terminal electrically connected to the second collector
plate and formed to pass through the cap plate, wherein a coupling
opening engaged with the second protrusion is formed in the second
electrode terminal.
[0020] After the second protrusion is engaged with the coupling
opening, it may be fixed to the second electrode terminal by
caulking.
[0021] The second protrusion may protrude toward the electrode
assembly from a bottom surface of the second horizontal part.
[0022] The second protrusion may be parallel to the second vertical
part.
[0023] As described above, the secondary battery according to the
embodiment of the present invention includes a collector plate
having a protrusion, and an electrode terminal having a coupling
opening engaged with the protrusion, thereby simplifying a coupling
structure of the collector plate and the electrode terminal.
Accordingly, the secondary battery according to the embodiment of
the present invention may reduce a volume occupied by the collector
plate and the electrode terminal within the case, thereby
increasing the capacity of the electrode assembly in a given
volume.
[0024] In addition, in the secondary battery according to the
embodiment of the present invention, the collector plate and the
electrode terminal are coupled to each other by laser welding and
the protrusion and the coupling opening are engaged with each other
to then be further coupled to each other by caulking, thereby
coupling and fixing the collector plate and the electrode terminal
in a more secured manner. Accordingly, the reliability of the
secondary battery can be improved.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] The above and other features and advantages will become more
apparent to those of ordinary skill in the art by describing in
detail exemplary embodiments with reference to the attached
drawings, in which:
[0026] FIG. 1 is a perspective view of a secondary battery
according to an embodiment of the present invention;
[0027] FIG. 2 is a cross-sectional view taken along the line I-I'
of FIG. 2;
[0028] FIG. 3 is an enlarged cross-sectional view illustrating a
portion `A` of FIG. 2;
[0029] FIGS. 4A and 4B are perspective views illustrating a state
in which a first collector plate and a first electrode terminal are
connected to each other; and
[0030] FIG. 5 is a cross-sectional view taken along the line II-II'
of FIG. 4A.
DETAILED DESCRIPTION
[0031] Example embodiments of the present invention will now be
described in more detail with reference to accompanying drawings,
such that those skilled in the art can easily practice the present
invention.
[0032] FIG. 1 is a perspective view of a secondary battery
according to an embodiment of the present invention, FIG. 2 is a
cross-sectional view taken along the line I-I' of FIG. 2, FIG. 3 is
an enlarged cross-sectional view illustrating a portion `A` of FIG.
2, FIGS. 4A and 4B are perspective views illustrating a state in
which a first collector plate and a first electrode terminal are
connected to each other, and FIG. 5 is a cross-sectional view taken
along the line II-II' of FIG. 4A.
[0033] Referring to FIGS. 1 to 5, the secondary battery 100
according to an embodiment of the present invention includes an
electrode assembly 110, a first collector plate 120, a first
electrode terminal 130, a second collector plate 140, a second
electrode terminal 150, a case 160 and a cap assembly 170.
[0034] The first electrode assembly 110 includes a wound or
laminated stacked structure having a first electrode plate 111, a
first separator 113, and a second electrode plate 112, and, may be
a thin plate or a thin foil shape.
[0035] The first electrode plate 111 may include a first electrode
collector formed of a metal foil made of, for example, aluminum
(Al), and a first electrode active material, such as, a transition
metal oxide, on the first electrode collector. In addition, the
first electrode plate 111 may include a first electrode uncoated
portion 111a where the first electrode active material is not
applied. The first electrode uncoated portion 111a may function as
a passage for current flowing between the first electrode plate 111
and an exterior of the first electrode plate 111.
[0036] The second electrode plate 112 may include a second
electrode collector formed of a metal foil made of, for example,
copper (Cu) or nickel (Ni), and a second electrode active material,
such as, graphite or carbon, on the second electrode collector. In
addition, the second electrode plate 112 may include a second
electrode uncoated portion 112a where the second electrode active
material is not applied. The second electrode uncoated portion 112a
may function as a passage for current flowing between the second
electrode plate 112 and an exterior of the second electrode plate
112.
[0037] The first separator 113 may be positioned between the first
electrode plate 111 and the second electrode plate 112 to prevent
electrical short circuits and to allow movement of lithium ions.
The first separator 113 according to this embodiment may be made of
a material selected from the group consisting of polyethylene,
polypropylene, or a copolymer of polypropylene and
polyethylene.
[0038] The first electrode assembly 110 and the second electrode
assembly 120 are accommodated in the case 160 with an electrolyte.
The electrolyte may include an organic solvent, such as EC, PC,
DEC, EMC, or DMC, and a lithium salt, such as LiPF.sub.6, or
LiBF.sub.4. In addition, the electrolyte may be in a liquid, solid
or gel phase.
[0039] The first collector plate 120 is made of a conductive
material, such as aluminum, and is coupled to the first electrode
uncoated portion 111a protruding from one end of the first
electrode assembly 110 to be electrically connected to the first
electrode plate 111. The first collector plate 120 includes a first
vertical part 121, a first horizontal part 122 and a first
protrusion 123. As used herein, the terms "vertical" and
"horizontal" are relative descriptors that are based on the
orientation of the battery as shown in FIG. 2 and describe a
generally perpendicular relationship between the components. It
will be appreciated that such descriptors apply even when in a
particular orientation of the battery, they may not extend in the
"vertical" or "horizontal" direction.
[0040] The first vertical part 121 is formed at one side of the
first electrode assembly 110 and is coupled to the first electrode
uncoated portion 111a. In one embodiment, the first vertical part
121 may be welded to the first electrode uncoated portion 111a. The
first vertical part 121 is formed to be perpendicular to the cap
plate 171 of the cap assembly 170 and to be parallel to a side
surface of the case 160.
[0041] The first horizontal part 122 is bent and extends from an
end of the first vertical part 121. The first horizontal part 122
extends horizontally parallel to the first vertical part 121. In
addition, the first horizontal part 122 is installed between a top
portion of the electrode assembly 110 and a bottom portion of the
cap plate 171. In other words, the first horizontal part 122 is
formed to be parallel to the cap plate 171. In addition, the first
horizontal part 122 is coupled to the first electrode terminal 130.
In one embodiment, the first horizontal part 122 may be coupled to
the first electrode terminal 130 by laser welding. In addition, a
first protrusion 123 is formed at a bottom portion of the first
horizontal part 122.
[0042] The first protrusion 123 protrudes from the first horizontal
part 122. In detail, the first protrusion 123 is formed on a bottom
surface of the first horizontal part 122 and protrudes toward the
electrode assembly 110 from the bottom surface of the first
horizontal part 122. Therefore, the first protrusion 123 is formed
to be parallel to the first vertical part 121. The first protrusion
123 may couple the first collector plate 120 to the first electrode
terminal 130. The first protrusion 123 is coupled to a coupling
opening 132b of the first electrode terminal 130. In one
embodiment, after the first protrusion 123 is coupled to the
coupling opening 132b of the first electrode terminal 130, it may
be fixed to the first electrode terminal 130 by caulking. In the
illustrated embodiment, one first protrusion 123 is exemplified,
but aspects of the present invention are not limited thereto. In
other words, a plurality of first protrusions 123 may be
provided.
[0043] The first electrode terminal 130 is made of a conductive
material, such as aluminum, and is coupled to the first collector
plate 120 to be electrically connected to the first electrode plate
111. The first electrode terminal 130 includes a first terminal
body 131 and a first terminal extension part 132.
[0044] The first terminal body 131 passes through the cap plate 171
and has a top portion riveted to be fixed to the cap plate 171.
[0045] The first terminal extension part 132 horizontally extends
from the bottom portion of the first terminal body 131 to then make
close contact with or to be close to the bottom surface of the cap
plate 171. A stepped part 132a being thinner than the first
terminal extension part 132 is formed at one side of the first
terminal extension part 132. The first horizontal part 122 of the
first collector plate 120 is coupled to the stepped part 132a. In
one embodiment, a sum of the thickness of the stepped part 132a and
the thickness of the first horizontal part 122 is equal to the
thickness of the first terminal extension part 132. In addition, a
coupling opening 132b is formed at a location of the stepped part
132a, corresponding to the first protrusion 123. In one embodiment,
each coupling opening 132b may be shaped to correspond to a
respective first protrusion 123. For example, if two first
protrusions 123 are formed, two coupling openings 132b may be
formed accordingly. In addition, when the first horizontal part 122
is coupled to the stepped part 132a, the first protrusion 123
formed on the bottom surface of the first horizontal part 122 is
coupled to the coupling opening 132b formed on the stepped part
132a. In addition, the first horizontal part 122 and the stepped
part 132a are coupled to each other by laser welding, the first
protrusion 123 is fitted into the coupling opening 132b, and the
first protrusion 123 is then fixed to the stepped part 132 by
caulking. Therefore, the first collector plate 120 and the first
electrode terminal 130 are firmly coupled to each other.
[0046] The second collector plate 140 may be made of a conductive
material, such as nickel, and is coupled to the second electrode
uncoated portion 112a protruding from the other end of the first
electrode assembly 110 to then be electrically connected to the
second electrode plate 112. The second collector plate 140 includes
a second vertical part 141, a second horizontal part 142 and a
second protrusion 143.
[0047] The second vertical part 141, the second horizontal part 142
and the second protrusion 143 of the second collector plate 140 may
have the same configurations and functions with the first vertical
part 121, the first horizontal part 122 and the first protrusion
123 of the first collector plate 120, and repeated explanations
will be omitted.
[0048] The second electrode terminal 150 may be made of a
conductive material, such as nickel, and is coupled to the second
collector plate 140 to then be electrically connected to the second
electrode plate 112. The second electrode terminal 150 includes a
second terminal body 151 and a second terminal extension part 152.
In addition, a stepped part 152a being thinner than the second
terminal extension part 152 is formed at one side of the second
terminal extension part 152 and a coupling opening 152b engaged
with the second protrusion 143 is formed in the stepped part
152a.
[0049] In addition, the second terminal body 151 and the second
terminal extension part 152 of the second electrode terminal 150
have the same configurations and functions with the first terminal
body 131 and the first terminal extension part 132 of the first
electrode terminal 130, and repeated explanations will be
omitted.
[0050] The case 160 is made of a conductive metal, such as
aluminum, an aluminum alloy, or nickel-plated steel, The case 160
may have an approximately hexahedral shape with an opening so that
the electrode assembly 110, a first collector plate 120, a first
electrode terminal 130, a second collector plate 140 and a second
electrode terminal 150 can be inserted and placed in the case 160.
In FIG. 2, the case 160 and the cap assembly 170 assembled to each
other are illustrated. As will be appreciated, the opening is a
substantially opened part of the case extending along a peripheral
edge of the cap assembly 170. The case 160 may have a polarity. For
example, the case 160 may function as a positive electrode.
[0051] The cap assembly 170 is coupled to the case 160. In detail,
the cap assembly 170 includes a cap plate 171, an electrolyte
injection opening 172, a plug 173, a safety vent 174, a gasket 175,
a terminal plate 176, a connection member 177, an upper insulation
member 178 and a lower insulation member 179.
[0052] The cap plate 171 may seal the opening of the case 160 and
may be formed using the same material with the case 160. The cap
plate 171 may be coupled to the case 160 by, for example, laser
welding. In one embodiment, the cap plate 171 may have the same
polarity as the case 160.
[0053] The electrolyte injection hole 172 is formed in the cap
plate 171, and an electrolyte is injected through the electrolyte
injection hole 172. The plug 173 seals the electrolyte injection
hole 172.
[0054] The safety vent 174 is formed in the cap plate 171 and is
thinner than the cap plate 171 so that it may be opened at a preset
pressure.
[0055] The gasket 175 is made of an insulating material and is
formed between each of the first electrode terminal 130 and the
second electrode terminal 150 and the cap plate 171 to seal a space
between each of the first electrode terminal 130 and the second
electrode terminal 150 and the cap plate 171. The gasket 175 may
prevent external moisture from infiltrating into the secondary
battery 100 or the electrolyte accommodated within the secondary
battery 100 from flowing out from the secondary battery 100.
[0056] The terminal plate 176 is coupled to each of the first
electrode terminal 130 and the second electrode terminal 150. In
addition, after the terminal plate 176 is coupled to each of the
first electrode terminal 130 and the second electrode terminal 150,
upper portions of the first electrode terminal 130 and the second
electrode terminal 150 are riveted, so that the first electrode
terminal 130 and the second electrode terminal 150 are fixed to the
terminal plate 176.
[0057] The connection member 177 is positioned between the terminal
plate 176 and the cap plate 171 and is formed to allow the first
electrode terminal 130 to be fitted thereto. The connection member
177 makes close contact with the cap plate 171 and the gasket 175
through the terminal plate 175. The connection member 177
electrically connects the first electrode terminal 130 and the cap
plate 171 to each other.
[0058] The upper insulation member 178 is positioned between the
terminal plate 176 and the cap plate 171 and is formed to allow the
second electrode terminal 150 to be fitted thereto. The upper
insulation member 178 makes close contact with the cap plate 171
and the gasket 175 through the terminal plate 175. The upper
insulation member 178 insulates the second electrode terminal 150
and the cap plate 171 from each other.
[0059] The lower insulation member 179 is formed between each of
the first collector plate 120 and the second collector plate 140
and the cap plate 171 and prevents unnecessary short circuits from
occurring. In detail, the lower insulation member 179 is formed
between the first horizontal part 122 of the first collector plate
120 and the cap plate 171. In addition, the lower insulation member
179 is formed between the second horizontal part 142 of the second
collector plate 140 and the cap plate 171.
[0060] As described above, the secondary battery 100 according to
an embodiment of the present invention includes the first collector
plate 120 having the first protrusion 123 and the first electrode
terminal 130 having the coupling opening 132b engaged with the
first protrusion 123, thereby simplifying a connection structure of
the first collector plate 120 and the first electrode terminal 130.
Therefore, the secondary battery 100 according to an embodiment of
the present invention can reduce a volume occupied by the first
collector plate 120 and the first electrode terminal 130 in the
case 160, thereby increasing the capacity of the electrode assembly
110 in a given volume.
[0061] In addition, in the secondary battery 100 according to the
embodiment of the present invention, the first collector plate 120
and the first electrode terminal 130 are coupled to each other by
laser welding and the first protrusion 123 and the coupling opening
132b are engaged with each other to then be further coupled to each
other by caulking, thereby coupling and fixing the first collector
plate 120 and the first electrode terminal 130 in a more secured
manner. Therefore, the secondary battery 100 according to an
embodiment of the present invention may have improved
reliability.
[0062] While the secondary battery of the invention has been
described in connection with a certain exemplary embodiment, it
will be understood by those skilled in the art that the invention
is not limited to the disclosed embodiments, but rather is intended
to cover various modifications included within the spirit and scope
of the appended claims and equivalents thereof.
* * * * *